The abstract play of light and color has always been fascinating, and over the last century a variety of optical, mechanical, electrical, and electronic devices have been disclosed to produce such effects automatically; in response to an audio input; or under the control of an operator.
At the turn of the century, complex effects could only be produced by optical means and "lumia" devices relied on the use of light-varying means such as filters and distorted reflective surfaces as the primary method of producing such effects.
Early non-mechanical systems such as that disclosed in U.S. Pat. No. 1,790,903 employed several circuits of colored incandescent light sources arrayed behind a translucent diffuser, the power supplied to such sources modulated in response to some characteristic of an audio signal. Over time the construction of the display unit has remained substantially similar (e.g. U.S. Pat. No. 3,845,468) but the complexity of the control system has increased. The division of the audio signal into several frequency bands has been the most common technique (e.g. U.S. Pat. No. 1,977,997), and other aspects of the audio signal, most notably the tempo or beat have been used in coordination with frequency-division to increase the complexity of the system's response.
While early systems employed a limited number of sets or circuits of light sources evenly disposed about the display and produced their abstract images solely by modulating the intensity of those circuits, many recent systems have employed two dimensional arrays of light sources in which each source may be separately controlled and the on/off condition of each light source in the array (a "pattern") can be stored in electronic memory for each of a number of such patterns. The lighting effect is therefore produced by the successive recall of patterns in order to form images moving across the surface of the display. The patterns displayed, the rate of movement, and the intensity of the display all may be altered in response to one or more aspects of the audio signal.
In order to increase the variety of lighting effects, recent systems have also employed separate aspects of the audio signal to control the pattern sequence and intensity (e.g. U.S. Pat. No. 3,806,873) and selectively combined two or more patterns by means of NAND (U.S. Pat. No. 4,056,805) or OR gates (U.S. Pat. No. 4,262,338) in order to produce new patterns related to more than one aspect of the audio signal.
It will, however, be recognized that variations in color, potentially one of the most expressive aspects of the lighting effect, are in modern systems, little more than incidental to the sequence of patterns and the modulation of their intensity in response to the audio signal.
It will further be recognized that construction of the display units associated with such systems is also comparatively crude, and that the variations possible in the appearance of the display unit itself (as distinguished from that in the sequence of patterns presented) are extremely limited.
It will also be recognized that while such devices are capable of complex pattern sequences, the determination of those sequences is made on the basis of a preprogrammed response to a given aspect of or given relationship between multiple aspects of an audio signal. No means is provided by which a light artist can exercise real time control in order to produce a light composition which bears a higher order relationship to, for example, a musical composition, one beyond the capability of any frequency, envelope, or tempo detector to duplicate.
It is therefore the object of the present invention to provide an improved visual display unit, whose construction affords a high degree of variety in its appearance, and in the range and subtlety of color effects possible, and further to provide the improvements to the control system required to make full use of these enhanced display capabilities and to permit an operator to exercise a heretofore unprecedented degree of control over a system capable of complex pattern sequence production.
It is a further object of the invention to make these capabilities available within a system which is economical to construct.